(19)
(11) EP 1 090 289 A1

(12)

(43) Date of publication:
11.04.2001 Bulletin 2001/15

(21) Application number: 99914272.2

(22) Date of filing: 30.03.1999
(51) International Patent Classification (IPC)7: G01N 29/04
(86) International application number:
PCT/US9906/886
(87) International publication number:
WO 9954/723 (28.10.1999 Gazette 1999/43)
(84) Designated Contracting States:
DE FR GB

(30) Priority: 20.04.1998 US 62906

(71) Applicant: NORTHROP GRUMMAN CORPORATION
Los AngelesCalifornia 90067-2199 (US)

(72) Inventors:
  • SHIVASHANKARA, Belur
    Bellevue, WA 98006 (US)
  • HUTTO, Fredrick, M.
    Stuart, FL 34996 (US)
  • ARCAS, Noe
    Plainview, NY 11803 (US)

(74) Representative: Maury, Richard Philip et al
Sommerville & Rushton,45 Grosvenor Road
St. Albans, Herts AL1 3AW
St. Albans, Herts AL1 3AW (GB)

   


(54) APPARATUS AND METHOD FOR MEASURING THE ACOUSTIC PROPERTIES OF ACOUSTIC ABSORBERS